The main theme of the article is ideal dimension of law. Author argue for a dual nature thesis – which contends that law necessarily comprises both a real or factual dimension and an ideal or critical dimension – and demonstrates how the ideal dimension (which refers primarily to moral correctness) implies the truth of non-positivism. The key provisions of the conception represented in article are substantiated in a polemic with other well-known representative of non-positivism – John Finnis.
 Particular attention is paid to determine relation between the real and ideal dimensions of law, which involves answering five questions. First, is there an outermost border of law? Second, is legal argumentation based exclusively on authoritative reasons or does it also include non-authoritative reasons? Third, what is the relation between human rights and legal systems? Forth, is democracy to be understood exclusively as a decision procedure or also as a form of discourse? Fifth, do legal system comprise only rules expressing a real “ought” or also principles expressing an “ideal ought”? These five questions are answered by the following five theses: the first with the Radbruch formula; he second with the special case thesis; the third with the thesis that constitutional rights are to be understood as attempts to positivize human rights; the fourth with the deliberative model of democracy; and the fifth with principles theory. All five theses turn on the same point: the claim to correctness.